Abstract: OBJECTIVE To investigate the effects of Xuemaitong Granules on expression of matrix metalloproteinases(MMPs) and matrix metalloproteinase inhibitors (TIMPs) in apoE-deficient mice.METHODS Male ApoE-deficient mice (n=33， aged 8 weeks， 18 to 20 g) on a C57BL/6J background， fed a high fat diet for 13 weeks. After confirming the atherosclerosis plaque formed， mice randomly divided into three groups: Xuemaitong Granules group， lipitor group and control group. After six weeks， venous blood and aorta were taken. The expression of MMP-2， MMP-9， TIMP-1 and TIMP-2 were measured by ELISA， Q-PCR and Werstern blot， respectively.RESULTS Compared with control group， the serum concentration of MMP2 and MMP9 significantly decreased (P<0.05) in two intervention groups and there was no significant difference(P>0.05) in them. The serum concentration of TIMP1 in Xuemaitong granules intervention group is much higher than in the other groups. However， The serum concentration of TIMP2 in the lipitor intervention group is much higher than that in the other groups. The same results were also detected by Q-PCR and Western blot in the aortic plaques.CONCLUSION Xuemaitong Granules can reduce the expression of MMP2 and MMP9 and up-regulate the expression of TIMP-1 in apoE-deficient mice.